Abstract: An apparatus and method of copy protection for use in digital data recorders such as DVD-RAM recorders, which includes embedding transmission time information into a digital data stream by digital watermarking and comparing the transmission time with the current time at the data recorder (30, 50). If the time difference is less than a threshold value it is presumed that the recording is for time-shifting purposes, namely recording a programme to watch later, which is generally allowed by copyright laws. If the time difference is greater than a threshold value it is presumed that the recording is an attempted unauthorized recording such as from a pre-recorded copy, and further recording is prevented.

Abstract: A technology of digital watermarking for binary images (including documents) is provided, which is capable of adjusting the amount of information to be embedded while avoiding the deterioration of image quality as far as possible. The watermark information is inserted by giving the standard for judgment of modification and the order of preference for modification according to the characteristic properties of the human visual sense for binary images and performing modification on pixels sequentially in the descending order of preference.

Abstract: An electronic document authenticity assurance technique and an information disclosure system both of which can compatibly realize the assurance of the authenticity of disclosure documents and the deletion of information inappropriate for disclosure. An electronic document is divided into constituent elements and an electronic signature is affixed to an arbitrary subset of a set including all the constituent elements. Otherwise, an electronic signature is affixed to data obtained by binding each of the constituent elements to information specifying the relationship between a respective one of the constituent elements and the structure of the electronic document. Otherwise, the hash values of the respective constituent elements are calculated and an electronic signature is affixed to data obtained by binding the calculated hash values together.

Abstract: A method of embedding information into contents includes a changeable range calculating step of obtaining a range where value change of the contents is imperceptible to the human being and a step of embedding information by changing the values of the contents within the changeable range.

Abstract: An authentication system for authenticating a particular individual using a recording medium containing information for identifying the individual has a recording medium issuing apparatus including, a database for storing a feature value usable for identification of the individual to be authenticated with the recording medium, means for managing the database to store the feature value of the individual to be authenticated with the recording medium and for generating search information to retrieve the feature value of the individual from the database, means for generating cryptographic information by encrypting the thus generated search information using a private key based on public key cryptography, and means for recording the thus generated cryptographic information and certification information concerning the individual onto the recording medium; and a recording medium authenticating apparatus including, means for decrypting the cryptographic information recorded on the recording medium using a public key

Abstract: A method and apparatus for embedding information into a target element in which information is to be embedded and a storage medium. The method and apparatus include obtaining plural sets of data values of a plurality of elements, wherein each set of data values is obtained along one direction extending through the target element, determining a strength of embedding information into the target element based on the plural sets of data values obtained, and embedding information into the target element based on the strength determined. The storage medium stores a program which enables embedding information by execution by a computer.

Abstract: A method for signature verification having a structure that reflects reliability of a signature history properly for a hysteresis signature used for verification based on the signature history. A method for arbitration and an arbitrator apparatus solve a dispute on correctness of a signature based on the method for verification. Furthermore, a method for managing history to migrate the management burden on a signer. Reliability is set on a signature issuing record that is a component of a signature history, reliability of the signature history is calculated based on the set reliability, and the calculated reliability is output as reliability of a verification result. The disclosure also provides a method for verification that reflects the reliability of a signature history properly and a method for arbitration and an arbitrator apparatus that solve a dispute on correctness of a signature. Furthermore, a signature history storage service apparatus mitigates the signature history storage burden on a signer.

Abstract: A method for using digital contents is provided. In the method, a request is made to a provider apparatus for a certificate containing a first provider ID embedded therein by a certification authority, and the certificate is received from the provider apparatus. A decision is made by using the certificate as to whether or not the provider is authorized by the certification authority. A request is made to the provider apparatus for a digital content having a second provider ID embedded therein by a contents guarantee authority when the provider is authorized by the certification authority, and the digital content is received from the provider. The first provider ID is read from the certificate, the digital content is correlated with the second provider ID, and the digital content is stored in a storage medium. The second provider ID is detected from the digital content in response to a request to use the digital content.

Abstract: A data embedding method and apparatus and a data reproducing method and apparatus are provided which can apply a digital watermark to various contents. Instead of embedding watermarking information in respective pixels or by using a relation between pixels, the watermarking information is embedded as a position pattern of changed pixels in the contents. Reliability comparable with conventional techniques can be obtained irrespective of a change in a smaller number of pixels for the contents.

Abstract: A reproducing method and apparatus for receiving and reproducing data and outputting the data into an external device. After reproducing the data, a descrambler corresponding to a type of the reproduced data is selected from a plurality of descramblers and the external device is authenticated by a selected authenticator which is included in a plurality of authenticators for authenticating the external device and corresponds to the selected descrambler, and the data is outputted.

Abstract: A digital watermark information is extracted from geometrically deformed image without using a calibrating digital watermark. Pixel data at positions predetermined in an X-Y coordinate used when embedding the watermark is extracted from image data in which the digital watermark has been embedded for given pixel data and compared with a reference value to determine whether the watermark has been embedded in the pixel data concerned or not. This processing is repeated until it is confirmed that the information is embedded in the pixel data concerned, while applying geometric deformation to the image data.

Abstract: A watermark information embedding method, and apparatus, capable of suppressing the quality degradation of contents and increasing the survivability of embedded information. When embedding watermark information in moving picture data formed of a plurality of still picture frames arranged in time series, a motion vector representing a property specific to moving picture is detected for each of image blocks generated by dividing a target frame. According to a motion quantity, a pixel change factor specifying rule is selected for each block. Out of pixels permitted to be changed in luminance depending upon the state of an image in each block representing a property specific to still picture, as many pixels as a number specified by the selected rule are selected. Luminance change processing for forming watermark information is conducted on the selected pixels.

Abstract: A method for managing genuine characteristics of both an electronic document and a print medium comprising: a step for recognizing image data contained in the electronic document; a step for applying an extraction condition of an image feature previously determined and must be considered to the recognized image data to calculate a coordinate set corresponding to a pixel or a set of pixels, constituting the image feature; a step for recognizing at least a coordinate value among coordinate values and pixel color values, corresponding to each of coordinates constituting the coordinate set, and for embedding the recognized coordinate value as a code of a digital watermark into the pixel or the pixel set, constituting the image feature, or into an area in the vicinity; and a step for outputting the electronic document where the digital watermark embedding process operation has been carried out to the print medium.

Abstract: There is provided a steganographic system which can dispense with an original image during extraction of watermark by determining a position at which an optimum space dependent physical quantity is embedded as a watermark complying with an image such that the picture quality can be prevented from being deteriorated, embedding watermark information in the image, generating information such as watermark embedding position information and receiving a watermark embedded image and watermark embedded position information to extract watermark information.

Abstract: When a video signal having electronic watermark information embedded therein is recorded on a recording medium, a reference signal is inserted in the video signal at a position different from a position of embedment of the electronic watermark information. The electronic watermark information is embedded in the video signal by alteration of a luminous value of a luminance signal included in the video signal. When the video signal is reproduced from the recording medium, a luminous value of the electronic watermark information is modified based on the reference signal.

Abstract: A system for distributing broadcast contents, in which the copyright of the broadcast contents can be protected, is provided. The system is a watermarking application system for broadcast contents copyright protection, constituted by a broadcasting station of broadcast contents, a broadcasting receiver of the broadcast contents, a network monitoring agent for monitoring secondary contents of the broadcast contents, a secondary content player for playing secondary contents, communication receivers for recognizing distribution of secondary contents, etc. Pieces of digital watermarking embedding equipment are provided in the broadcasting station and the broadcasting receiver respectively. Pieces of digital watermarking extraction equipment are provided in the network monitoring agent and the secondary content player. Particularly, the broadcast contents are outputted through an analog output or an internal disk.

Abstract: When watermark information is embedded in moving image data formed of plural still image frames arranged in time sequence, the motion vector and deformation quantity (motion estimation data) of each block in the current frame are estimated. By using this motion estimation data in both digital watermark embedding process and encoding process, it is possible to make watermark embedding and encoding faster while suppressing the degradation of the content and improving the survivability of the embedded information.

Abstract: The present invention can detect watermark information from motion picture of various scanning methods and various picture sizes without causing increase of a memory capacity.

Abstract: A digital watermark information judging method is provided for detecting digital watermark information which is embedded in at least one element of digital data by altering at least one data value of the element. The method first estimates the data value of the element by using data values of at least two neighboring elements of data located near the element, then compares the estimated data value with an actual data value of the element to detect the amount of the alteration, and judges the presence and value of the digital watermark information based on the amount of the alteration.

Abstract: A recording device which is capable of preventing alteration of a generated digital picture data and suitable for improving the reliability of the digital picture data as an evidence. The recording device includes a related information embedding unit for embedding a related information on the digital picture data stored in a related information storing unit in the digital picture data obtained by a picture receiving unit by means of the digital watermarking technique, a digital signature generating unit for generating a digital signature of the digital picture data in which the related information has been embedded, and a recording unit for adding the digital signature to the digital picture data in which the related information has been embedded and storing it in a memory unit.